The SuperMac Spectrum/8 LC video card is an accelerated 8-bit video card for the LC PDS (Processor Direct Slot). It originally retailed at US$799 and was MacUser’s third choice video card/19″ display option in the February 1992 roundup of LC PDS solutions.

The Spectrum/8 LC supports 1-bit (black and white) through 8-bit (256 colors from a 16 million color palette or 256 shades of gray) video on resolutions from 512 x 384 to 1152 x 882.

Supported resolutions for the Spectrum/8 LC PDS video card (from the manual):

• 512 x 384 pixels (Apple 12″ RGB)
• 640 x 480 pixels @ 67 Hz 640 x 870 pixels (Apple Portrait Display)
• 832 x 624 pixels @ 75 Hz
• 1024 x 768 pixels @ 60 Hz
• 1024 x 768 pixels @ 75 Hz
• 1152 x 870 pixels @ 75 Hz
• 1152 x 882 pixels @ 72 Hz (Radius 19″ 72 Hz Trinitron Display)

The following displays are listed as compatible in the owner’s manual. This list is not exhaustive:

• 12″ Macintosh RGB Display
• 12″ Macintosh Monochrome Display
• 13″ Apple High Resolution Monitor
• 13″ Apple Color Display
• Macintosh Portrait Display
• 21″ Macintosh Two Page Monochrome Display
• 16″ Trinitron Display
• 19″ Dual-Mode Trinitron Display
• 19″ RasterOps
• 19″ Radius
• 19″ SuperMac Color Display
• 19″ SuperMac Platinum Display
• 21″ Platinum Two Page Display
• 21″ SuperMac Two Page Color Display

The Spectrum/8 card is not well suited to drive an Apple 21″ Monochrome Display due to a lack of contrast.

SuperMac Video Card FAQ

Most of this is adapted from the Spectrum Graphic Cards Q&A that used to be available online.

Are SuperMac Spectrum Cards Compatible with System 7.5?

Yes, as long as your SuperMac card is being used with recent ROM and software versions. If your card is too old to support the 3.0 or 1.7.2 ROMs, it may not be fully compatible. The exception are due to Apple’s CloseView control panel, which does not work properly with SuperMac cards. That said, CloseView is redundant since almost all SuperMac cards already have a superior built-in zooming feature. If CloseView was custom-installed during System 7.5 installation, you should remove it from the Control Panels folder.

My Color Monitor Boots into Black and White

A SuperMac video card will start up in Black & White mode if Apple’s Display Enabler extension and Monitors control panel version 7.3.2 or later are used with a graphics card containing any ROM version prior to version 3.0.

My Color Monitor Won’t Boot in Grayscale

Because of a CPU bug in the Macintosh LC, the Spectrum/8 graphics card will come up in color mode after a restart, even if it was set to gray shades before, unless LCINIT (provided with the Spectrum software) is installed in your System Folder. [Download SuperMac drivers from Macintosh Repository.]

My Screen Redraws Incorrectly

If you already have ROM version 3.0 on your card, check to make sure that you have SuperPower v1.1 installed within your Extensions folder in your System Folder.

Can I Switch Resolution on the Fly?

SuperMac cards support “on-the-fly” resolution switching through the Monitors control panel, provided you have a multi-resolution display and SuperMac ROM version 3.0 or later, SuperVideo 3.0 or later, Monitors control panel v7.3.2 or greater, and Apple’s Display Enabler 1.0 or greater. (If you are running System 7.5 or later, you do not need to install Display Enabler separately). The required Apple software files are part of Apple’s MultipleScan Display software package.

Can I Support Two Monitors?

It may be possible to support two displays, one with the Mac’s built-in video and one with this video card.

Sources

• Spectrum/8 LC Card, Retro Technology

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